I have a weird issue that only seems to be affecting IE 7. The web site is a 3.5 c# asp.net website that utilizes ajax and the ajax control toolkit deployed to a win 2003 server. Everything appears to be correct in the web.config. In fact, everything works perfectly in IE6 and Firefox 3. It is only in IE7 that I get the dreaded sys is undefined error.
Also, the site appears to be working fine for IE7 on a different installation of the same code. That server is running win 2003 with very similar setups.
Since this appears to be a server issue, are there any kind of settings that would prevent ajax-enabled sites from displaying properly in IE7?
Believe it or not, but emptying the temporary internet files solved the problem. I hate things like this!